In an electronic device such as a modem and a power supply circuit, a number of electronic components are mounted. For example, there are many cases in which a capacitor is used for the purpose of noise removal, cut of a direct current component, and so on.
Here, miniaturization, realization of low cost are requested for electronic devices, and along with this, also as to electronic components, miniaturization, realization of low cost are requested. Furthermore, there are many cases in which surface mounting electronic components are desired for the purpose of reduction of mounting cost due to automatic mounting and reduction of a mounting area. On one hand, there occurs many cases in which conflicting specifications such as realization of high performance, reduction of characteristic fluctuation, and what is more, improvement of endurance are requested, in concert with miniaturization.
Furthermore, along with realization of multiple pins for LSI etc. and an increase of bit number of a signal line, there arises the need of high-density mounting for mounting a plurality of electronic components in such a place that a line interval is very narrow.
In particular, there are many cases in which two lines for data input and data output are paired in a modem etc., and there is need to surely mount two electronic components on a line.
In order to satisfy these, electronic components, which were worked out variously, have been proposed (e.g., see, JP-A-2001-110691 publication, JP-A-2002-43170 publication).
In particular, as descried in the above-described patent documents, it was carried out to raise breakdown voltage by covering an element with an external covering material such as resin in order to respond to high breakdown voltage, and to improve endurance, heat resistance, and moisture resistance, and so on, in electronic components.
However, in this case, there is need to form the external covering material by use of a metal mold etc., and there are many cases taking such a configuration that two pieces of the formed external covering materials are bonded, and lead terminals are protruded from a laminated surface thereof, and so on. However, in the suchlike configuration, there were many cases in which the number of man-hours for production thereof becomes large, and cost becomes expensive. In addition, terminal portions and lead terminals are to be protruded from a midstream portion of a side surface of the external covering material, and therefore, there was such a case that it takes cost for fine adjustment thereof, and so on.
In order to respond to this, an electronic component, which is manufactured by putting a thing which is in such a state that terminal portions, or lead terminals were connected to an element, in a frame, pouring resin etc. in this frame, and sealing it as an external covering material, has been proposed.
FIGS. 41 and 42 are side views of an electronic component in relevant art, and it is of a shape as a result of taking a manufacturing method as described above, and there is such a merit that it can be manufactured at low cost.
1100 designates an electronic component, and 1101 designates an element which includes various things such as a capacitor (single plate capacitor, multilayered capacitor etc.), a resistor, a coil, a filter, and other electronic devices. 1102 designates an internal electrode in case that the element is the multilayered capacitor, and 1103 designates an external electrode, and 1104 designates a lead terminal, and 1105 designates an external covering material. Meanwhile, the lead terminals 1104 which are connected to the element 1101 and protruded from the external covering member 1105, are called as terminal portions in case that they are directly connected to the element, and terminals, which are further connected to the terminal portions directly connected to the element, are called as lead terminals, but there is no rigid distinction there, and they are similar things.
As apparent from FIG. 41, in the electronic component 1100 which was externally covered by pouring resin in a frame in order to realize low cost as described above, the lead terminals 1104 thereof become of such a shape that they are protruded from corner portions of a bottom surface and side surfaces of the external covering material 1105 to an outside.
However, in electronic components in relevant art as represented in FIG. 41, terminal portions and the lead terminals 1104 are protruded from the corner portions of the bottom surface and the side surfaces of the external covering material 1105, and therefore, there is no allowance (margin) between the external covering material 1105 and the lead terminals 1104 etc., and there was such a problem that flexure resistance against vibration and shock from an outside after mounting is weak.
In addition, as a matter of course, there is no capacity to deal with shock etc., and therefore, the shock is concentrated on the external covering material 1105, a mounting solder portion etc., and there was such a problem that endurance etc. are weak such as there occurring damage such as cracks, and so on.
In addition, as shown in FIG. 42, it becomes easy for warpage and bending to be generated on the lead terminal 1104 which was protruded to an outside, and there occurred such a problem that mounting to a substrate becomes difficult, and mounting reliability becomes low.
In addition, in order to manufacture at low cost, such a thing that the lead terminals 1104 were connected to the element 1101 is placed in a metal mold etc., and melted resin etc. is poured into an inside of this metal mold, and thereby, it is molded, but in the suchlike manufacturing method, there is need to place it in a metal mold in such a state that the lead terminals 1104, which are protruded, were raised upwardly, i.e., in such a state that it was reversed, and to pour resin etc. therein. On this account, it is difficult to have the lead terminals 1104 protruded from side surfaces. Alternatively, in order to have them protruded from side surfaces and further to make allowance (margin) hold between the protruded lead terminals 1104 and the external covering material 1105, there is need to fold back the lead terminals 1104 intricately in advance, and therefore, there was also such a problem that adjustment etc. become complex, and low cost is not realized.
As above, in a method of pouring resin in the element 1101 and the lead terminals 1104 which were placed in a frame to realize external covering, for electronic components in relevant art, reduction of the number of man-hours, fine adjustment after the fact etc. are unnecessary, and therefore, it is possible to realize low cost, but there was such problems that capacity to deal with flexure of lead terminals becomes weak, and endurance and shock resistance become low, and mounting reliability and shape holding performance at the time of transport become low, and so on. On this account, there was such a problem that electronic components are insufficient from the view point of actual practical use.
Further, in electronic components in relevant art as represented in FIG. 41, it becomes very high temperature on the occasion of pouring melted resin, and therefore, there was such a problem that the internal electrode 1102 of the multilayered capacitor 1106 is melted, damaged and so on. Also in case of automatically mounting the electronic component 1100 by re-flow etc., it becomes high temperature in the same manner, and therefore, melt and damage of the internal electrode 1102 became a problem. On this account, it was requested to use the internal electrode 1102 to which high temperature countermeasure is applicable.
In addition, in the electronic component represented in FIG. 41 in relevant art, unlike a case of sealing with the external covering material by a method of transfer mold etc., the lead terminal 1104 is not protruded from a side surface of the external covering material 1105 and a protruded portion of the side surface to an outside, and therefore, there was such a problem that shock resistance and endurance, flexure resistance of the lead terminal 1104 are weak.
On this account, there is such a problem that reliability at the time of manufacture, transport and mounting, and after mounting is weak, and there was such a problem that electronic components are insufficient from the view point of actual practical use.